Device for connecting a wiper arm to a wiper blade and wiper arm and wiper blade using such a device

ABSTRACT

The invention relates to a device to connect a wiper arm ( 12 ) to a wiper blade ( 14 ) featuring a supporting element ( 16 ) holding a wiper strip ( 20 ) on which a base element ( 30, 60 ) is fastened as the first part of a coupling device, whereby the wiper arm ( 12 ) is embodied to be U-shaped and overlaps the base element ( 30, 60 ) with its U-shape and whereby holding means ( 42, 72 ) are embodied on the wiper arm ( 12 ) within its U-shape, which holding means form a second part of a coupling device and cooperate with the first part of the coupling device. It is proposed that the holding means ( 42, 72 ) be embodied as articulated means for holding the wiper blade ( 14 ) in an articulated manner, which can also transmit a bearing force ( 44 ) on the wiper blade ( 14 ) to be exerted by the wiper arm ( 12 ) on the wiper blade ( 14 ) in an operating position and which are at least approximately completely covered by the wiper arm ( 14   4 ).

STATE OF THE ART

[0001] The invention relates to a device to connect a wiper arm to awiper blade according to the species of the main claim. With known wiperblades of this type (EP 0 753 439 A1), a wiper arm is divided into aninner wiper arm as well as an outer cap. The inner wiper arm is composedin a conventional manner of a solid arm section and a spring-loadedarticulated part linked to it, which extends into the area in which awiper blade can be attached. The cap extends over the wiper arm, the capfirst supporting itself on a solid part of the wiper arm and secondlyextending up to the end of the wiper blade in the area above the linkagepoint for the wiper blade. The cap features a connection for the wiperblade so that the wiper blade is fixed in position. The bearing pressurefrom the wiper arm to the wiper blade is transmitted, however, by theextension of the inner wiper arm. An intermediate piece is inserted forthis providing the connection between the wiper arm, cap and wiperblade, which requires an additional axis for this. Due to the greatnumber of individual parts, this structure is very expensive for one andsecondly not favorable for assembly.

ADVANTAGES OF THE INVENTION

[0002] The device in accordance with the invention having the featuresof the main claim has the advantage that the wiper arm is designed to bea single part and in the process takes on the positioning of the wiperblade, transmission of the pendulum motion required for the wiperoperation, transmission of the bearing pressure as well as formativeelements. Fastened to the wiper blade is a base element, which takes onthe task of the conventional axis and cooperates together with the wiperarm after the wiper arm and wiper blade have been connected. Anintermediate part to secure or position the connection is not required.As a result, the assembly and disassembly of wiper arm and wiper bladeis simple and quick both during initial assembly of the overall systemas well as during subsequent replacement of the wiper blade by the enduser.

[0003] Advantageous further developments of the device according to themain claim are possible due to the features listed in the sub-claims.The connection is designed particularly simply if the base elementfeatures at least two wings extending in the direction of the U-base ofthe wiper arm, said wings featuring counter holding means correspondingto the holding means in the sense of an articulated connection. The baseelement can be executed as a simple plate-bending stamped part that canbe manufactured cost effectively and can be fastened to a supportingelement of the wiper blade. This base element can be connectedpermanently and therefore captively to the wiper blade and assumes thefunction of the articulated axis of the wiper blade that is otherwisestandard and to be provided at additional expense.

[0004] Instead of an articulated axis, it is proposed that the counterholding means be embodied as projections or openings. These thencorrespond with the holding means of the wiper arm and thereby replace,as mentioned, the articulated axis that is otherwise standard.

[0005] If the holding means are embodied on the sides of the U-legs, ithas proved to be advantageous to provide projections for these. If thewiper arm is made of plastic, the projections can be formed simply,directly on the inside of the U-legs using injection molding technology.These means of connection are not visible from the outside.

[0006] In addition to the holding means formed on the inside, additionalprojections can be attached that are adjacent to the wings of the baseelement in the assembly position and guide this element with a lowamount of play. This makes particularly quiet wiper operation possible.

[0007] Improved guidance is produced if the holding means are embodiedas counter wings extending at a distance from the U-legs, the counterwings overlapping with the wings of the base element in the assemblyposition. This produces a gap between the U-legs and the counter wingsinto which the wings of the base element can be inserted. Depending uponthe width of the gap, a certain play or a certain pressure can begenerated between the wings and the counter wings. For this reason thecounter wings are embodied somewhat elastically so that they deflect andtherefore can accept tolerances.

[0008] The wiper blade can be clipped into or engage in the wiper armvery simply if the holding means and/or the counter holding meansfeature bevels or roundings. It is also conceivable, however, for theholding means or the counter holding means to feature openings withholes in the direction of the counter holding means or holding means.These holes could have a narrowing, which then makes engaging in thecorresponding projections of the counter holding means or holding meanspossible. Under some circumstances, an axis can be advantageous insteadof projections for this.

DRAWINGS

[0009] Two exemplary embodiments of the device in accordance with theinvention are depicted in the drawings and explained in more detail inthe following description. The drawings show:

[0010]FIG. 1A wiper blade engaged in a wiper arm in a diagonal view,

[0011]FIG. 2 Wiper arm and wiper blade according to FIG. 1 in anunengaged position,

[0012]FIG. 3A view according to III in FIG. 2,

[0013]FIG. 4A section along line IV-IV in FIG. 5 according to the secondexemplary embodiment,

[0014]FIG. 5 Along line V-V in FIG. 4 without a wiper blade,

[0015]FIG. 6A base element according to the second exemplary embodimentin a diagonal representation and

[0016]FIG. 7A view diagonally from below into a wiper arm according tothe second exemplary embodiment.

[0017] The individual figures are not drawn using the same scale.

DESCRIPTION

[0018]FIG. 1 depicts a wiper system 10 with a wiper arm 12 and a wiperblade 14. The wiper blade 14 features a supporting element 16, which iscomprised of two strips 18, which lie in longitudinal grooves of a wiperstrip 20. The longitudinal grooves are arranged in a head area 22 of thewiper strip 20, adjacent to a wiper wedge 26 featuring the wiper lip 24,which is connected with the head area 22 via a rocker bridge 28.

[0019] The wiper blade 14 in FIG. 1 is drawn in an extended form, as itoccurs for example when the wiper blade 14 is guided over a very evenwindow. In its relaxed shape that forms when lifted away from thewindow, the wiper blade 14 is bent in such a way that the wiper strip 20lies in a concave inner side of the supporting element 16. When placingthe wiper blade 14 on a window, the ends of the wiper blade 14 therebycontact first the window and, once there is additional pressure, theentire wiper blade lies against the window. The supporting element 16with this kind of pre-bent shape thereby replaces the expensivesupport-bracket system of known bracket-mounted wiper blades.

[0020] A base element 30 also overlapping the head area 22 of the wiperstrip 20 is attached to the supporting element 16 (FIG. 2). The baseelement features a basic body 32, which bridges over the supportingelement 16 as well as the head area 22 of the wiper strip 20 and claws34 are formed on its outer ends, which surround the strips 18 of thesupporting element 16 with a form fit. The base element 30 is alsowelded to this form-fit with the supporting element 16, whereby a solidhold of the base element 30 on the supporting element is guaranteed, onthe one hand, and the strips 18 are held in the longitudinal grooves ofthe wiper strip 20, on the other hand.

[0021] Extending from the base body 32 of the base element 30 are twowings 36 that extend away from the supporting element 16 approximatelyparallel and perpendicular to the base body 32. The base element 30thereby represents a first part of a coupling device to connect thewiper blade to the wiper arm.

[0022] The wiper arm 12 is designed to be U-shaped with a U-base 38,onto which two U-legs 40 extending in the direction towards the wiperblade 14 are attached (FIG. 2). As shown in FIG. 1, the U-legs 40completely overlap the base element 30 in the assembly position betweenthe wiper arm 12 and wiper blade 14. Even in the longitudinal extensionthe wiper arm 12 overlaps the base element 30. In FIGS. 1 and 2, thewiper arm 12 is guided only until shortly after the area of theconnection to the wiper blade 14, but in another development it can alsoreach the end of wiper blade 14 thereby covering the wiper blade 14completely.

[0023] Holding means 42 are embodied on the wiper arm 12 within itsU-shape, which form a second part of a coupling device, and whichcooperate with the first part of the coupling device in the assemblyposition (FIG. 1).

[0024] The holding means 42 of wiper arm 12 cooperate with the wings 36of the base element 30 in the assembly position in such a way that thewiper blade 14 can twist relative to the wiper arm 12. The holding means42 are therefore articulated means for holding the wiper blade 14 in anarticulated manner. A bearing force 44 on the wiper blade 12 ¹ to beexerted by the wiper arm 12 on the wiper blade 14 in the operatingposition is transmitted via the holding means 42, which effect a fixingof position of the wiper blade 14 relative to the wiper arm 12. Thebearing force is generated by a spring that is not depicted here, whichis applied, on the one hand, to the wiper arm 12, thereby representing aspring-loaded articulated part, and to a solid arm section, on the otherhand.

[0025] A circular projection 46 is formed on each of the wings 36 of thebase element 30, which extend towards one another, and are counterholding means, which correspond to the holding means 42 in the sense ofan articulated connection. The holding means 42 are embodied in thisregard as counter wings 48, which extend at a distance 50 essentiallyparallel to the U-legs 40. In the assembly position, the wings 36 of thebase element 30 overlap with the counter wings 48 of the wiper arm 12.In the overlapping region the projections 46 are arranged on the wings36 so that in the assembly position they project into the openings 52correspondingly arranged in the counter wings 48.

[0026] When assembling the wiper blade 14 that is already fastened tothe base element 30 with the wiper blade 14 ², the wiper blade 14 isguided onto the wiper arm 12 from below until the wings 36 are adjacentto the counter wings 48. Then the wiper blade is moved perpendicular toits longitudinal extension in the direction of the wiper arm 12 so thatthe wings 36 dip into the distances 50. As soon as the projections 46reach the area of the counter wings 48, the counter wings 48 deflectuntil the projections 46 catch in the openings 42 when the wiper blade14 is guided further up. The projections 46 are provided with bevels orroundings 54 in order to make deflection easier. Naturally, these canalso be provided on the lower end of the counter wings 48.

[0027] In a second exemplary embodiment according to FIGS. 4 through 7,the same parts are provided with the same reference numbers.

[0028]FIG. 4 depicts a section of a wiper arm 12 holding a wiper blade14 via a coupling device. A base element 60 (FIGS. 4 and 6), which has aU-shape matching the inner contour of the wiper arm 12 with a U-base 62and U-legs 64, is fastened on the wiper blade 14. Attached to the U-legs64 are claws 66, which surround the strips 18 of the supporting element16 when the base element 60 is connected with the wiper blade 14. Alsoin this case the base element is welded to the supporting element.Projections 68 extending in the direction of the inside of the U-leg 40of the wiper arm 12 are attached to the U-legs 64, which, as seen fromthe claws 66, extend, like the wings 36, in the direction of the U-base38. The projections 68 feature central openings 70.

[0029] Projections 72, which project into the openings 70 of the baseelement 60 in the assembly position, are formed on the insides of theU-legs 40 that face one another. The projections 72 are smaller in theirlateral extension than the openings 70 and are adjacent to the openings70 on one side in the assembly position. The U-base 62 of the baseelement 60 is removed in an area near the projections 68 and the U-legs74 of the base element 60 are raised in an arched manner in thedirection of the U-base 38 of the wiper arm 12. In the assemblyposition, this results in freedom of movement of the wiper blade 14against the wiper arm 12 around a contact point between the inside edgeof the opening 70 and the outside edge of the projection 72, therebypreventing the base element 60 from yielding because the U-legs 64 areadjacent to the U-base 38 of the wiper arm.

[0030] In order to keep lateral play to a minimum or to eliminate itcompletely, along with the projections 72, additional, strip-likeprojections 74 are formed on the insides of the U-legs 74.

[0031] For simpler assembly, the projections 72, which serve as holdingmeans, feature bevels or roundings 76. If, when assembling the wiperblade, the base element 60 is introduced between the U-legs from below,the U-legs 40 deflect laterally until the projections 72 come to lie inthe openings 70.

[0032] While in the case of the first exemplary embodiment both localpositioning as well as transmission of the bearing force 44 take placebecause of the cooperation of the projections 46 with the openings 52,in the second exemplary embodiment, though positioning is achieved bythe cooperation of the openings 70 with the projections 72, transmissionof the bearing force 44 is achieved, however, by the cooperation of theU-base 38 with the base element's 60 U-legs 64 that continue in thedirection of the U-base 38.

[0033] It should still be mentioned that the described openings can beformed by molded cavities in individual cases, which makes itunnecessary to require punching out actual holes during themanufacturing process.

[0034] A wiper arm 12 in accordance with the invention is characterizedin that it features a U-shape inside of which holding means arearranged, which can cooperate with counter holding means of the wiperblade. The holding means are either embodied as counter wings 48, whichextend from the U-base into the area encompassed by the U-shape, or asprojections 72, which extend starting from the inside of the U-leg 40.It is also conceivable to provide both counter wings 48 as well asprojections 72 in combination on the inside of the U-legs 40.

[0035] A wiper blade according to the invention is characterized in thatit features a base element 30 or 60 overlapping a supporting element 16,which has wings 36 or equally acting U-legs 64 featuring projections 46or openings 70. These wings 36 and/or openings 70 are designed in such away that they cooperate with holding means 42 of a wiper arm 14 ³ ascounter holding means and can provide an articulated connection.

1. Device to connect a wiper arm (12) to a wiper blade (14) featuring asupporting element (16) holding a wiper strip (20) on which a baseelement (30, 60) is fastened as the first part of a coupling device,whereby the wiper arm (12) is embodied to be U-shaped and overlaps thebase element (30, 60) with its U-shape and whereby holding means (42)are embodied on the wiper arm (12) within its U-shape, which holdingmeans form a second part of a coupling device and cooperate with thefirst part of the coupling device, characterized in that the holdingmeans (42, 72) are embodied as articulated means for holding the wiperblade (14) in an articulated manner, which can also transmit a bearingforce (44) on the wiper blade (14) to be exerted by the wiper arm (12)on the wiper blade (14) in an operating position and which are at leastapproximately completely covered by the wiper arm (12).
 2. Deviceaccording to claim 1, characterized in that the base element (30, 60)features at least two wings (36, 64) extending in the direction of theU-base (38) of the wiper arm (12), whose wings feature counter holdingmeans (46, 70) corresponding to the holding means (42, 72) in the senseof an articulated connection.
 3. Device according to claim 2,characterized in that the counter holding means are projections (46, 68)or openings (70).
 4. Device according to one of the preceding claims,characterized in that the holding means (42, 72) are embodied asprojections (72) on facing sides of the U-legs (40) of the wiper arm(12).
 5. Device according to claim 4, characterized in that along withthe holding means (72) additional projections (74) are attached, whichare adjacent to the wings (64) of the base element (60) in the assemblyposition.
 6. Device according to one of claims 1 through 3,characterized in that the holding means (42) are embodied as counterwings (48) extending at a distance (50) from the U-legs (40), whichcounter wings overlap with the wings (36) of the base element (30) inthe assembly position.
 7. Device according to claim 6, characterized inthat the wings (36) extend between the U-legs (40) and the counter wings(48) in the assembly position.
 8. Device according to one of thepreceding claims, characterized in that the holding means (42, 72)and/or the counter holding means (36, 68) feature bevels (72) orroundings.
 9. Wiper arm containing one part of a device according to oneof claims 1 through 8 on the wiper-arm side.
 10. Wiper blade containingone part of a device in accordance with the invention according to oneof claims 1 through 8 on the wiper-blade side.